The loss of resistance to broomrape by the majority of domestic and foreign hybrids, that are resistant to the 5 th race of the parasite (E) in the Black Sea and Azov regions of the country indicates that from about 2004-2005 there appeared new (more virulent) races of the parasite (Orobanche cumana Wallr.). Maternal lines of sunflower hybrids have been developed whose stability to a new race of broomrape is controlled by one dominant gene, Org. These lines have a high ability of combination on the main economic grounds.
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